The regulatory region of the biotin operon in Escherichia coli

Abstract
The biotin anabolic operon in E. coli is apparently transcribed divergently from 2 partially overlapping face-to-face promoters. A mutation that increases transcription in vivo creates an additional promoter in vitro. The putative operator contains an imperfect palindromic sequence that partially overlaps the promoters. The regulatory and genetic implications of these findings are discussed.